Determination of the partial specific volumes of thermoreversible gelatin/water and κ-carrageenan/water gels

✍ Scribed by Helmut Cöulfen; Werner Borchard

• Book ID: 102939105
• Publisher: John Wiley and Sons
• Year: 1994
• Tongue: English
• Weight: 619 KB
• Volume: 195
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.1994.021950405

✦ Synopsis

Abstract

In this paper systematic density measurements of gelatin/water and κ‐carrageenan/water gels are presented in a wide range of concentrations and temperatures. From about 600 measurements for gelatin/water and about 500 measurements for the system κ‐carrageenan/water empirical relations for both systems have been derived which allow to calculate the densities of these gels in a limited concentration range if the temperatures and the polymer weight fractions are known. The calculated densities have an accuracy of better than 0,001 g/cm^−3^ compared with the directly measured densities. If the extrapolated partial specific volumes of the pure polymer are plotted against the temperature, a jump with an inflexion point can be detected at about 23–24°C for both systems. These data indicate a Λ‐type transition of the expansion coefficient α for both systems at 23–24°C although there are still too few data to make clear conclusions.